The document summarizes the results of a group chemistry experiment investigating factors that affect the rate of chemical reactions. The experiment tested how changing concentration, temperature, surface area, and use of catalysts influenced the rates of various reactions. It was found that increasing concentration, temperature, and surface area, and adding catalysts increased reaction rates. Catalysts were shown to speed up reactions without being used up in the process.

1. Final Report: Group 3

2. 1. Determine the factors that affect the speed
or rate of chemical reactions.
2. Demonstrate how these factors can affect
the rate of a chemical reactions
3. Apply the collision theory to explain the
rates of chemical reactions

3. RANK METAL OBSERVVATION CHEMICAL
EQUATION
5 Cu Nothing
Happened
Cu + 2HCl ->
CuCl2 + H2
2 Fe Forms into
green
viscous
2Fe + 6HCl ->
2FeCl3 + 3H2
4 Zn It keeps
reacting
Zn + 2HCl ->
ZnCl2 + H2
3 Al It keeps
reacting
2Al + 2HCl ->
2AlCl + H2
1 Mg Completely
disolve
Mg + 2HCl ->
MgCl2 + H2
 Explain how the nature of
reactants affects the rate of the
reaction in terms of the activity
series of metals and hydrogen.
-The elements have their different solubility

4. RANK METAL OBSERVATION
2 Powder
Zinc
It dissolves
slower and
more heat
1 Mossy
Zinc
It dissolves
faster and
least heat
SAMPLE mL Starch-sulfite
mL KIO3 mL H2O TIME(SEC)
Standard
run
1 1 8 14sec
1 1 2 7 17sec
2 1 3 6 18sec
3 1 4 5 13.5sec
4 4 1 5 3.5sec
5 3 1 6 2sec
6 2 1 7 12sec
BALANCED EQUATION
Zn + 2HCl -> ZnCl2 + H2
BALANCED EQUATION
Mg + 2HCl -> MgCl2 + H2

5.  Based on the above
observation, explain the effect
of changing the concentration
on reaction rates.
- the higher the concentration of
reactants, the faster the
reaction will proceed. This is
simply because there are more
molecules to react, so the
likelihood of them colliding is
increased.
 What is collision theory? Briefly
explain the observation using
this theory.
-it explains that gas-phase chemical
reactions occur when molecules
collide with sufficient kinetic
energy.

6. SAMPLE MEDIUM
REACTION
TEMPERATURE
TIME OF
REACTION
Standard
Run
Room
temperature
35 c 61 sec
1 Ice bath 10 c 15 min
2 Warm
water
bath
40 c 121 sec
 What effect does
temperature have on
reaction rates?
-the higher temperature
the faster reaction is.

7. SAMPLE OBSERVATION
RELATIVE
RATE OF
REACTION
Without
CuSO4
The zinc
turns into
bubble but
not
dissolving
With CuSO4 The zinc
turns silver
into
brownish
 What gas is formed in the above
reaction? What effect did CuSO4
have on the reaction between
zinc and sulfuric acid?
- If bubbles are produced faster
from zinc and dilute sulfuric acid
in the presence of copper metal,
then it must be the copper metal
that makes the difference and
acting as a catalyst.
BALANCED EQUATION
Zn + H2SO4 -> ZnSO4 + H2

8. SAMPLE OBSERVATION
RELATIVE
RATE OF
REACTION
Without
amylase
White
viscous
With
amylase
White
viscous w/
bubbles
 Which of the reactants used is
responsible for the observed
color? What is the role of
amylase in the reaction?
- the amylase acts a catalyst and
breaks the starch down to the
sugar maltose at a certain
temperature.

9.  What is a catalyst? Based on your above
observations, what can you conclude about the
effect of adding a catalyst on chemical reactions?
- to initiate or accelerate the rate of a chemical
reaction.

10.  Other than those illustrated in the experiment, give two reactions that
occur very slowly (those that take longer time, for instance takes
several days for the reaction to occur). Give also two examples that
occur rapidly.
- In the experiment that we perform, the slowest reaction between the two
or more compound is that the powder zinc in the 6M HCl, while the
rapidly react on the compound is that the magnesium in the HCl solution.

11.  List down the factors that influence reaction rates and for each factor,
cite a practical example and tell whether the reaction is desirable or
not. If it is undesirable, suggest means of preventing the reaction to
happen.
-Concentration effects which two substances cannot possibly react with
each other, Temperature effects which increasing the temperature of a
system increases the average kinetic energy of its constituent particles,
Surface Area effects when two reactants are in the same fluid phase,
their particles collide more frequently than when one or both reactants
are solids, Solvent effects which can also affect the reaction rates of
solute particles like sodium acetate solution reacts with methyl iodide,
and Catalyst effects often determine the product of a reaction by
accelerating only one of several possible reactions that could occur.

12.  Distinguish between homogeneous catalysis, heterogenous catalysis
and enzyme catalysis. Provide an example for each, show chemical
equations when possible.
- In a heterogenous reaction, the catalyst is in a different phase from the
reactants. While in a homogeneous reaction, the catalyst is in the same
phase as the reactants.